A sample holder for soft x-ray absorption spectroscopy of liquids in transmission mode

Abstract

A novel sample holder for soft x-ray absorption spectroscopy of liquids in transmission mode based on sample cells with x-ray transparent silicon nitride membranes is introduced. The sample holder allows for a reliable preparation of ultrathin liquid films with an adjustable thickness in the nm-μm range. This enables measurements of high quality x-ray absorption spectra of liquids in transmission mode, as will be shown for the example of liquid H(2)O, aqueous solutions of 3d-transition metal ions and alcohol-water mixtures. The fine structure of the x-ray absorption spectra is not affected by the sample thickness. No effects of the silicon nitride membranes were observed in the spectra. It is shown how an inhomogeneous thickness of the sample affects the spectra and how this can be avoided.

Ionic Solutions Probed by Resonant Inelastic X-ray Scattering

“…The XA spectra show the characteristics water features, namely the pre-edge (∼ 535 eV), the main-edge (∼ 538 eV) and the post-edge (∼ 540 eV) as reported by previous studies [7,11,12,39].…”

“…The experiments were performed at the beamline U41_PGM and U49/2-PGM 1 of the synchrotron radiation source at the Helmholtz Zentrum Berlin using the FlexRIXS [38] and Transmission NEXAFS [39] endstations and at P04 of PETRA III at DESY site in Hamburg using the ChemRIXS endstation. X-ray absorption measurements in transmission mode were performed with a liquid cell [38].…”

Intrinsic deviations in fluorescence yield detected x-ray absorption spectroscopy: the case of the transition metal L2,3edges

“…This is strongly dependent on the specific symmetry, in other words on the 3d count, the crystal field effects and also the charge transfer effects. Figure 3 shows that 3d 1 , 3d 3 3d 5 , low-spin 3d 7 , 3d 8 and 3d 9 have relatively high FY-XAS integrated intensity, compared with the relatively low FY-XAS intensities of the other 3d counts. For example, the Mn 2+ system reaches a set of intermediate states that have a larger-than-average integrated x-ray emission decay strength, but it is not evident to explain the trends in this behavior.…”

“…c) Low-spin octahedral symmetry for 3d 4 , 3d 5 , 3d 6 and 3d 7 systems. d) Comparison with experimental spectra for 3d 6 , 3d 7 and 3d 8 …”

“…Transmission measurements are less often applied because the strong absorption cross sections imply the need of a uniform sample thickness below in the order of 1 micron 2,3 . Only Often xray microscopy experiments regularly make use of transmission experiments mode 4,5 and since the first application of transmission mode XAS to water by Yang and Kirz in 1985 6 approaches have been developed recently for transmission mode detected XAS of water and aqueous solution [7][8][9][10][11][12][13] . Still, most 2p XAS experiments are performed with EY measurements, that use drain current, total electron yield detectors (i.e.…”